A used liquid logic 10-12’ sit-ins can usually be had for less than $400 if you find a good deal. I found my wife a Liquid Logic Stingray 12 for $250 bucks, It’s got a sealed single bulkhead, plenty of room for slightly larger paddlers, stable, comfortable, yet agile in calm waterways. Something like this might fit the bill at your current weight, till you get to your ideal weight and is looking for another better-fitting kayak in medium volume range and would then know exactly what the next kayak to get is based on your needs til then.
I predict you’ll love the new eyeballs as much as I love mine. 15 months after having the same surgery I am still elated daily at not having to locate, wipe down and perch glasses on my extremely myopic peepers every morning and then tend to them all day, especially in hot weather and when I am active. Paddling has been greatly enhanced by not having to constantly clear condensation, sweat and splashes from what used to be requisite glasses, or fretting about losing a $400 pair in a capsize.
Not to mention the enhanced clarity and color vision from having my old yellowed biological lenses removed. I remember leaving the clinic the day of the second surgery and seeing the world outside like when Dorothy in “The Wizard of Oz” awakens in her black and white tornado tossed house and opens the door to the Technicolor Emerald City.
Judging by your athletic outlook and production, I think you should step up to an introductory sea kayak. Anything less and you will be bored of it in a few months.
Don’t worry if it is a little shaky, you will overcome that.
The Perception Carolina, or Necky Looksha would probably fit that bill and the used market has a mess of them for fairly cheap.